The present invention relates to packaging and, more particularly, to point-of-sale paperboard packaging.
Paperboard packaging is well known in the packaging art. A typical paperboard package is constructed from pre-cut sheets of paperboard (often called “blanks”). A conventional blank is a single, continuous sheet of paperboard having a shape dictated by the number and arrangement of panels included in the package. The blanks are often pre-scored or otherwise configured to define fold lines that facilitate folding of the blank into the desired shape. The blank will typically include one or more retaining flaps that can be used to permanently secure the blank in the folded configuration or to temporarily secure a closure, such as a lid, in the closed position. For example, a conventional paperboard package may include a retaining flap that is attached to another panel by adhesive or fasteners (e.g. staples) to permanently secure the blank in the shape of the package. The use of adhesives and/or fasteners has a number of drawbacks. For example, adhesives and fasteners increase cost and complicate the manufacturing process. Costs are increased not only by the cost of the adhesive and the fasteners, but also by the cost of the equipment required to apply the adhesive or install the fasteners. Additionally, the use of adhesive can have a significant negative impact on the environment. For example, many adhesives utilize solvents and other potentially toxic components. Also, the presence of adhesives can complicate efforts to recycle the paperboard package. Further, the integrity of an adhesive bond can be impacted by delamination of the paperboard, and the strength of a staple bond can be limited by the tear-strength of the paperboard. As a result, in applications where the attachment is required to bear a significant amount of weight, it may be necessary to use more expensive paperboard with greater delamination strength and/or greater tear strength.
In addition to permanent attachments, retaining flaps are also used with temporary attachments. For example, it is often desirable to provide a package with a lid that can be repeatedly opened and closed to selectively provide access to the contents of the package. To provide this functionality, the package may include a top closure with a retaining flap that can be fitted into the package to temporarily hold the top closure in the closed configuration. In this context, the retaining flap may have small slits that interlock with internal flaps that help to hold the top closure in the closed position. These types of temporary joints have limited hold strength and, if used without supplementation, typically prevent the package from being suspended by a hanging tab secured to the top closure because the weight of the package can pull open the top closure. This is a particularly significant drawback in the context of point-of-sale packaging where it is often desirable to suspend packages from a hanging hook.